Computing devices such as personal computers, laptop computers, tablet computers, cellular phones, and countless other types of Internet-capable devices are becoming increasingly prevalent in numerous aspects of modern life. Over time, the manner in which these devices are providing information to users is becoming more intelligent, more efficient, more intuitive, and less obtrusive. With advancements in technology, computing devices continue to become smaller and more adaptable. Some computing devices, such as wearable computing devices, enable a user to have hands free use while operating the device.
In some examples, wearable computing devices are able to place miniature image display elements close enough to the eyes of a user such that the displayed image fills or nearly fills the field of view of the user. To the user, the displayed image appears as a normal sized image, such as might be displayed on a traditional image display. The relevant technology may be referred to as “near-eye displays.” Near-eye displays are fundamental components of wearable displays, such as on a head-mountable device (HMD). An HMD may place a graphic display close to one or both of the wearer's eyes and enable a user to use eye gestures to send commands to the HMD to execute tasks.